1. Field of the Invention
The present invention relates to a droplet jetting apparatus for jetting an ink droplet onto an object, and a display device manufacturing method of forming a pixel of a display device by jetting the ink droplet.
2. Discussion of the Background
In case the display device such as an organic EL (Electro Luminescence) display, or the like is manufactured, the ink serving as the material of the luminous layer is jetted and then the pixel is formed by this ink.
As an example of such ink applying method, the method of generating a minute droplet of the ink and then jetting this droplet onto the object such as the substrate, or the like (referred appropriately to as an “I/J method” hereinafter) may be listed (see Patent Application Publication (KOKAI) 2002-221617, for example).
However, when there is some trouble in the application head that jets the ink, in some cases an adequate amount of ink cannot be jetted. According to an extent of such trouble, sometimes the ink cannot be jetted at all.
For instance, as shown in FIG. 1, when there is some trouble in a nozzle E of an application head 115 or an ink chamber corresponding to the nozzle E, a stripe irregularity (luminance nonuniformity) 91 is generated on a substrate 109 owing to the non-jetting of the ink or the lack of ink to be jetted, which is caused due to such trouble (these are referred appropriately to as a “jet malfunction” hereinafter). This results in a marked reduction in the quality of the organic EL display, or the like.
Also, when the Ink jet is carried out, it is checked in advance whether or not the jet malfunction is being generated. In this event, sometimes the jet malfunction is generated after the ink jet is actually carried out. If such malfunction cannot be sensed at once, it is continued to manufacture the substrate, or the like, on which the stripe irregularity is generated as described above. As a result, no non-defective product can be manufactured after the generation of the jet malfunction.
However, it is difficult to sense immediately the jet malfunction without fail.